Road-roller.



R. E. B. OROMPTON & B. T. J. TAPP.

ROAD ROLLER.

APPLIOATION FILED JULY 17, 1913.

Patented Nov. 11, 1913.

4 SHEETS-SHEET 1.

R. E. B. GROMPTON 6: E. TL'QT. TAPP.

ROAD ROLLER.

APPLIUATION FILED JULY 17, 1912.

1,078,533, Patented Nov. 11, 1913.

4 SHEETS-SHEET 2.

R. E. B. CROMPTON & E. T. J. TAPP.

ROAD ROLLER.

APPLICATION FILED JULYI'T, 1912.

1,078,538, Patented Nov. 11, 1913.

4 SHEETS-SHEET 3.

R. E. B. GROMPTON & E. T. J. TAPP. ROAD ROLLER.

APPLICATION FILED JULY17, 1913.

1,078,538, Patented Nov. 11, 1913.

4 SHEETSSHEET 4.

FIG. IO. FIG, I],

Flo. I2. Flo; l3.

6; $56 S I Z 7za'e71/i 0r6 Warne% UNITED STATES PATENT OFFICE.

nooims EVELYN BELL onion-Pros KIND nnmnsr THOIEAS: mums IE2, of Lemon,

- ENGLAND.

ROAD-ROLLER.

t rones.

specification of Letters Patent.

Application filed. July L7; 1913; Serial No. 779,615.

i To all who-m z't may concern."

Ilti

Be it known that we, Rooms \ETVEILYN BELL CRDMFTON and Enmisw THoMAs JaMns TAPE, subjects of the King of Great Britain, residing at Thriplands, Kensington; Court,

London, England, and 'Z Manville road,

Waves upon the road surface. The effect of,

this; phenomenon is serious: for; Water tends to collect in thetroughs of the Waves andto run off the road, thereby rendering those portions of theroad softer and more liable to Wear'out quickly than are the summits of the Waves. shown that the periodor length-between successive Wave summits bears a relation to the distance between the'axles of the rollers; andit has been found in practice to be im possible toeli-Ininate the Waves, once they have been formed; hy'any means other than rolling in a di-rectlon transversely of the road or street Which-is only possible a. very few localities.-

This invention has for its object to over-' come: these disadvantages by so distributing the Weight over the surfaceto-be rolled and consolidated that it' is finished his more perfeot manner and with a longitudinal contour more free from" recurring" undulations or Waves than has hitherto been found: possible. To this end the Weight of the roller is distributed over more than two axles spaced at unequal distances apart. Means may be provided so as to vary the incline? tion of some of the rollers for the purpose of producing banked surfaces.

A road roller constructed in accordance with the invention mayhave three, lieu-r,-v

five or more axles a-ndcorresponding rollers,

but it is found that the desired results can be attained satisfac-torilywith a roller Wl161@-' of the Weight is distributed over three axles whereof the distance separating? the axle at Practical observations have.

one extremity and the center axle is greater than the distance separating the center axle and the axle at the other extremity. 'lhe' frameby which the Weight isdistributed over the rollers is constructed so as to be very r gid-ma verticaldirection and" the dis.- lLLflbU-hlOll of the Weight can be so arranged if desired that each of the axles carries approximately one-third of the total weight;

According to one construction three rollers of sufficient Width may be mounted in alinementin a frame carrying the weight and source of motive power.- Or instead of this arrangement a large roller may be mounted on an axle disposed near thementerof the frame andcarrying approximatelyonethird or more of theweight as hereafter mentioned and the front or rear aXles'In-ay each be provided with a; pair of rollers blamed side by. side and{ of small diameter, all arrangedso ratenteaNovn anions.

Ill

that their tracks to'some extentoverlapsthat ofthe center roller. In anotherarrangement single rollers may be mounted on the front and rear axles, and a pair ofrollers (eonstituted by broad flat tiredwheelsi may be carried by the center axle; the distribution of the weight over the various axles being as described above By the center roller of large diameter and'those oi the twoend axles of smaller diameter the end axles which must, for steerage purposes, be ar ranged tobe pivoted, can becarried on turntablesor their equivalent With-great facility; the turntables being supported on prolonganone of the upper memberof; the main; frame. In cases Where it is desirable to roll roadways curved in plan-it may be desirable to provide means for inclining the plane of the steering turntables in relation to the plane of the center roller, as in this Way banked orconical surfaces can be producedbyrolling and with great accuracy. The angle of inclination of these steering turntables can be made adjustable to suit the circumstances of each case:-

It will be seen that with three axles so rigidly connected and the Weight so rigidly supported that even if the road roller be used on an existing undulating or' wavy surface the three axle roller will have a tendency to correct this waviness as at the time that the centerroller passes over a hollow its weight will. be partly transferred to the two end rollers which are on the summits thereby causing extra compression-ah these siderable portion of the weight on that end which are used for-the roller will be transferred to the center roller. In this manner it is possible to produce more uniformly even and more uniformly consolidated road surfaces possessing greater wearing properties than have hitherto been possible with the apparatus usually employed.

In carrying out the invention, although we may use any number of axles eater than two, it will be simplest to describe the method of carrying it out by using three axles only, and the accompanying drawings show three alternative arrangements of using three axles in such a manner as to eifect our purpose.

In the drawings, which are diagrammatic for the sake of simplicity, Figurel is a side elevationand'Fig. 2 is a plan view of one arrangement. Fig. 3 is a side elevation and Fig. 4 1s a lan viewof a second arrange ment, and Flg'. 5 is a side elevation and Fig.

dis" a plan of a third arrangement. Figs. 7 a'nd8 are diagrammatic views illustrating the application of the roller to an uneven surface. Fig. .9 is a diagrammatic view showing a freshly laid surface in course of compression by a roller constructed in accordance' with the invention. Figs. 10, 11, 12 and 13 show various means'whereby the inclination of the axles or the steering pivots may be varied and controlled for the purpose of producing banked surfaces.

The first method is shown in Figs. 1 and 2; where three single rollers, A, B, C, on three axles a, b, a, are used one to each axle, the center roller serving as the propelling roller, the power being transmitted as shown diagrammatically from the engine d by means of 'a-cha-in e. the two end rollers A, G, being secured to the frame or chassis f by means of the forked turntables g, h, purpose of steering the roller. I

The se'cond'method is shown in 3 and 4 which illustratefive rollers A A, B, C, and C arranged'with-the single'roller B on the center axle band the pairs of rollers A ,'A C G on the two end axles 0:, 0, respectively." The front axle a and rear axle 0 turn about two pins P and P passing from the frame 7 through the blocks 0 and O to which they are attached for purposes of steering. In this type also the drive is preferably taken by the center roller in any convenient manner.

The third method, shown in Figs. 5 and 6 is carried out by means of an arrangement of four rollers a pair B B being mounted on the center axle b and one roller A and C on each of the end axles a and 0 respectively. Here we also show an alternative method of providing for the steering of the end rollers by means of the turntables y, 717

surrounding the end rollers A and C. This arrangement has the advantage that a very low frame can be used; the two center rollers B B can be utilized for the propulsion of the apparatus and a differential gear Z can be mounted either on the axle b'itself, or an alternative arrangement maybe adopted, by mounting these center rollers B B so as to revolve independently on their axle and be driven by a countershaft which would be provided with a differential gear.

The rollers may be of equal'or varying diameter but it is advisable that the axle taking the drive, should when necessary be required to support more than one third of the weight and that the roller or rollers attached to this axle should therefore have a greater area of contact with the road than the others.

v In some instances it may be necessary to arrange that all the rollers are driving rollers in which case power can be transmitted to the steering roller by bevel gears through the steering axles, or an arrangement of flexible couplings or other equivalent mechanical devices or hydraulic -or electricalmeans of'driving may be used.

In order that the center driving axle F) with its roller or rollers may bring suflicient weight to propel the whole machine when, owing to irregularity of the road surface said center axle supports less than its own share of the total weight of the roller,

said center axle is so attached and fixed as 0 i to allow itto sink so far that its lower rolling surface may be below the corresponding surfaces of the end rollers, and so remain in contact with the road, but this vertical play must be confined to the downward direction 105 so that the roller cannot rise above a certain point relative to the frame of the machine as indicated in Fig. 7, where the front roller 0 is shown passing over the summit of a convex or high point-on the road surface (which would cause the center roller B if confined rigidly in place tolose part or the'whole of its insistant weight of its adhesion and consequent driving power) and where the roller B is therefore shown to 5 have sunkbelow its normal position (indicated by the dotted lines) down to the po; sition shown by full lines. When however this center roller B in turn passes over the same high point as shown in Fig. 8, an insurface is satisfactorily obtained. The same 125 result may be obtained by allowing one or both the end rollers to rise above but not to fall below a certain point relative to the frame.

In Fig. 9 there is shown a three axle roller B above referred to.

compressing freshly laid road material and it w1ll be seen that the pointsof contact of the rollers with the material are not in the a same horizontal alinement and that although the rollers are of equal diameter their axles are during this operation not necessarily in the same plane. This is due to the lowering of the normal position of the center roller We can obtain the same action by allowing one or both of the end axles a, o to rise above their normal position although they are constrained so as not to fall below a fixed point relative to the frame.

In all the three arrangements shown we consider it imperative that the axles be unevenly spaced apart a. e. the distance from the axle a to the axle Z2 should'not be the same as the distance from b to a. We find this necessary to prevent the production of any form of recurring wave on the road surface which if once commenced might con: tinue to set up rhythmical or harmonic undulations with increasing intensity but which is obviously impossible with the irregularly spaced axles.

In rolling curved and banked-surfaces such as occur on motor or cycle racing tracks and which it may be advisable to apply in some cases to ordinary highways, it is necessary that the steering axles or the pivots of the front and rear axles a; and 0 should be arranged so that they may be inclined in the vertical plane, this angle of inclination allowing all the rollers to rest squarely and fairly all over their contact line upon the surface that is required to be rolled. This angle of inclination of the steering axles is determined by the angle of the banking, by' the radius of the curve, and -b the wheel base of the roller. It must there ore be made adjustable withinlimits and we can provide means of doing this by several well known mechanical devices such as are illustrated by Way of example in Figs. 10, 11, 12 and 13. In Figs. 10 and 11 alternative methods of varying the inclination of the steering pivots are illustrated. Thus, in Fig. 10 a rear \vardly extending lever m is attached at one end to the steering crown n and at its opposite end is formed with a screw-threaded aperture taking over and adapted to work as a nut upon a correspondingly screw- -threaded rod 0 mounted in a blockp suprods 9 and 1"v is adapted to be caused by means of a suitable spanner, tommy bar or the like to draw the rods 9 and 7' together or to separate same so as to incline the steering forks; Fig.12 shows the application of the mechanism illustrated in Fig. 10 to'a -roller constructed with turn-tables as in Figs. 5 and 6, and this modification operates similarly to that described with reference to Fig. 10. Fig. 13 shows a modified device for inclining the turn tables, which consists of a shaft a mounted in bearings u, u, disposed on the chassis and having solid therewith a worm '1; which meshes with a worm wheel 20 solid 'with the turn-table. The shaft 15 may be provided with squared ends to receive a key or spanner for the purpose of turning same. Either of these constructions may be arranged. at both ends of the apparatus. In practice the driver of the roller will be provided with the requisite data to enable him to adjust the steering pivots or the turntables-to produce banking of the desired 'angle, and before starting to roll the particular surface he will regulate or set the inclination of the steering pivot-s or turntables accordingly. By thus inclining the steering pivots or turn-tables the front and rear rollers will be constrained to rest squarely on the road when the apparatus is steered upon a curve and will thus produce a banked surface. If desired indicating mechanism may be provided in connection with these inclining devices in order to enable the driver to set same for certain stand ard conditions.

What we claim is:-

1. Rolling apparatusv for producing true surfaces on roadways and for other purposes, comprising a body carrying more than two axles, said axles being arranged at unequal distances apart, and rollers mounted upon said axles.

2. Rolling apparatus for producing true surfaces on roadways and for other purposes, comprising a body carrying more than two axles, said axles being arranged at unequal distances apart, some of said axles being capable of vertical displacement in a downward direction relatively to said body 5 and being limited in regard to vertical displacement in an upward direction, and rollers mounted upon said axles.

3. Rolling apparatus for producing'truc surfaces on roadways and for other 'pur- 12o poses, comprising a body carrying more than two axles, said axles being arranged at unequal distances apart, some of said axles being capable of verticaldisplacement in a downward direction relatively and being limited in regard to vertical displacement in an upward direction, some of said axles bein fixed in regard to vertical movement relatively to said body, and rollers mounted upon said axles. 1 g

to said body 4. Rolling apparatus for producing true surfaces upon roadways and for other pur-' 5. Rolling apparatus for producing true.

surfaces upon roadways and for other purposes, comprising. a body carrying more than two axles, said axles being arranged at unequal distances apart, rollers mounted upon said axles, and means to incline the endmost rollers to cause said rolling apparatus to produce curved and banked surfaces.

6. Rolling apparatus for producing true surfaces upon roadways and for other purposes, comprising a body carrying more than two axles, said axles being arranged at unequal distances apart, some of said axles being capable of vertical displacement in a downward direction relatively to said body and beinglimited in regard to vertical displacement in an upward direction, rollers mounted upon said axles, and means to incline some of said rollers to cause said rolling apparatus to produce curved and banked surfaces.

7. Rolling apparatus for producing true surfaces on roadwaysand for other purposes, comprising a. body carryingmcre than two axles, said axles being arranged at .unequal distances apart, some of said axles being capable of vertical displacement in a downward direction relatively to said body and being limited in regard to vertical displacement in an upward direction, some of said axles being fixed in regard to vertical movement relatively to said body, rollers mounted upon said axles and means to incline some of said rollers to cause said rolling apparatus to produce curved and banked surfaces.

8. Rolling apparatus for producing true surfaces onr'oadways and for other purposes, comprising a body carrying more than two axles, said axles being arranged at unequal distances apart, some of said axles being capable of vertical displacement in a downward direction relatively to said body and being limited in regard to vertical displacement in an upward direction, some of said axles being fixed in regard to vertical movement relatively to said body, rollers mounted upon said axles, and means to incline the endmost of said rollers to cause said rolling apparatus to produce curved and banked surfaces.

In testimony whereof we have hereunto set our hands in presence of tWo subscribing witnesses.

ROOKES EVELYN BELL GROMPTON. ERNEST THOMAS JAMES TAPP.

WVitnesses:

EUSTACE H. BARKER, ARTHUR '1. WAGHORN. 

